MINERAL ID LAB: DRY XRF & XRD ANALYSIS

MINERAL ID LAB: DRY XRF & XRD ANALYSIS

MINERAL ID LAB: DRY XRF & XRD ANALYSISNote: Anything marked in gray is filled in by the instructor. All other fields, checks, and write-ups to be completed by you!

Name: Course section ID

Date received: Due Date:

The following Due Date Penalty applies: -10% / day G 100% or ______%

Overall DRY XRF & XRD ANALYSIS LAB Grade: %

/50

Lab Access Badge #: Lab safety training completed on:

Maintenance Infraction(s): Q Warning Only! Q -5% Q -10%Q -15% and Lab Revocation

Assigned Lab Equipment BIN number:

Assigned PLM number:

Refer to Manual of Rapid Mineral Identification - Volume I: Mineral ID Tests and Determinations12.1.2 Semiquantitative Handheld XRF (X-ray Fluorescence) p.9112.2 XRD POWDER DIFFRACTION ANALYSIS p.94

ASSIGNMENTS: I am using the client sample alternate sample

/10 COMPOSITION & LAYOUT - one or multiple point deduction per infractionThe appearance is neat and orderly. The lab is typed and graphics and data are electronically

prepared and analyzed. Subscripts and superscripts are appropriately used and equations are explained. Thelab is complete with all fields populated. Graphics and data are placed in a coherent form. Proper formattedcitations are included.

/10 WRITING & GRAMMAR - one point deduction per infractionSpelling and grammar are correct. Word repetition and use of first person language is avoided.

Statements are factually correct. Appropriate and complete language becoming to a client report is used..

/10 EXECUTION & DATA COLLECTION - one or multiple point deduction per infractionAppropriate procedural execution of the lab is evident from the writing and data. Procedural detail is

adequately mentioned. One or multiple controls are used and described to identify the integrity of the data.Any inconsistencies are mentioned and explained.

/10 GRAPHICS & ILLUSTRATIONS - one or multiple point deduction per infractionAt minimum a graphical representation of the lab set-up and/or execution is required. All illustrations

must be electronically prepared. Pictures should be clear, of high quality, and with neutral background.Graphs should have a title with appropriate axis and unit labels. Citation of source must be included. Graphics

need to meat minimum resolution (300 DPI) requirements.

/10 CONTROL, ACCURACY & PRECISION - one or multiple point deduction per infractionA control to establish accuracy and precision must be used. For numerical data collection, precision

must be calculated and presented. If applicable, an explanation should be given why accuracy was notestablished.


ALL ANSWERS MUST BE TYPED USING A WORD PROCESSOR! This includes chemicalformulas, equations, tables and special characters. Become intimately familiar with these functions inyour preferred word processor. Where graphics are indicated insert the proper graphic or picture. Befamiliar with placing and sizing visuals into a written document. Attach your completed document(s)to this sheet!

LAB PROCEDURE: You may work with a partner for collecting data and running the lab experiments.However, this is NOT a group project. Each individual in the group is responsible for his/her own labwrite-up, which includes OWN pictures, data tables, graphics, etc.! Do NOT copy and share except forRAW data!!!

For ALL assignments use a citation's database:

ZOTERO citationsdatabase

ZOTERO is a citations database thatincorporates itself into Word and yourBrowser.

Free open source softwareavailable athttps://www.zotero.org/

Note: You may use a different citations database, if desired. But you MUST use a citations database!

NOTE: After downloading and installing ZOTERO, take an hour or two to become familiar with the operation of the software. One of your firsttasks will be to set the citation style to the United States Geologics Survey (USGS) format in ZOTERO. The USGS citation systemwill be required for this course and your final product.

Loading the USGS citation format into ZOTERO: Once Zotero Standalone is installed, click on "Preferences" under theEdit tab. Once there click on "Cite" and go to the "Styles" tab. Click on the "Get additional styles..." below the Styles MangerBox. When the Zotero Styles Repository Window opens, click on the "geology" button within the "Fields" section. A list ofgeology journals should now appear. Scroll down to the U.S.Geological Survey and click on it. The U.S.G.S style will nowbe part of your Zotero system and you can set your citations to be formatted accordingly in Zotero.

General Writing Instruction Summary:

• Use professional language, which means AVOID first person expressions such as “I”, “we”, “our”. Use normal prose,active voice and third party language. Do NOT use informal wording, contractions, jargon, slang terms, or superlatives.Exclude similes/metaphors (and humor!)

• Use present tense to report well accepted facts, e.g. 'Pyrite is a sulfide mineral'. Use past tense to describe specific results,e.g. 'When acid was applied, the specimen effervesced'

• Be quantitative wherever relevant (stats, numbers etc.).

Subscript &Superscript

Use appropriate subscript and superscript, especially when it comes to chemical formulas andmathematical units..Acceptable examples: 2.9 g/cm3, H2O, PO43-, ag=9.8m/s2

Unacceptable examples: 2.9 g/cm3, H2O, PO4 3-, ag=9.8m/s^2

• Use precise concrete language, no ambiguity e.g, ‘correlated’ � ‘related’. Use simple language – no unnecessary “frills”(distractions). Pay attention to sentence structure and grammar

COMPILING TABLES, FIGURES and EQUATIONSGRAPHICS are the heart of any report. Nothing is more true than in science that a picture is worth a thousand words. Alwayscompile graphics first and then write your text focusing on your graphic. In order to create good graphics and photographs, followthe instructions below.

Cameras and Photos: Cell phones with a 7.2MP camera are usually ok. When taking pictures, lighting and background is key. This means dark objectsshould be photographed with light or white backgrounds (sheet of paper) and visa versa for light objects. Having adequate lightingwill also help to get sharp, crisp, in focus pictures. Blurry and out of focus pictures are not acceptable.

https://www.zotero.org/


Graphics: You should be able to modify, enhance, annotate or overlay graphics. Minimum resolution is 300dpi. Make sure graphics are crisp,clear and any label is easily readable. All graphics should have a caption stating the author and/or citation. Preferably use losslessgraphic formats, such as .tif or .bmp. Unfortunately .jpg is NOT lossless and will degrade a little every time you open and save itagain in order to manipulate picture contents.

Graphics Editor Software: You will need a graphics editor and learn how to use it. Windows comes with itsdefault Windows Paint editor. It is found in the Windows Accessories Folder. For a more advanced option withmany more professional features you may try GIMP: https://www.gimp.org/ This is a FREE, open source imageeditor working across all computing platforms (Windows, Apple, Linux, etc.). The software comes with ampledocumentation and examples on how to manipulate any picture or graphic.

Screen Capture Software: A screen capture or snipping software is advantageous in order to only grab the partof a graphic from the screen that is important or necessary. Windows 10 comes with a default snipping tools,

such as “Snip & Sketch” found in its own folder or “Snipping Tool” found in the Windows Accessaries Folder.Note: When snapping a picture, make sure it is large enough on the screen to capture enoughpixels to have adequate resolution for the final product.

NOTE: Compiling acceptable and good looking graphics and photographs is very involved and can not be rushed. These are oftenthe heart of any report and should be compiled BEFORE writing. Last minute thrown together graphics will without doubt loweryour grade on the client report significantly.

COMPOSITION, LAYOUT, WRITING & GRAMMAR SUMMARY

LanguageThe following list is an example of common faults in language usage and attribution.

Errors / Mistakes / Faults Examples with margin Fault Counts & Codes

Spelling:incl. capitalization errors & spacing

Grammar:incl. punctuation, superfluouswords, transpositions

Style:incl. paragraph,repetitive expressions / wordserroneous expression / words,sub- or superscription,unprofessional style,word insertion

Sentence:incl. grammar, run-on,strings of nouns

| | The mineral florite has a mohs hardness of four. | Nicolas Steno was trained in the classical texts on science.

| Isometric crystals are also isotropic Here light propagates at the samespeed.| | Rocks are composed of many many minerals mixed.

|Para. ... in the geologic sciences.¶Near the end of the 19th a new theory ...|||rep ... is a light colored mineral. These light colored minerals are often light... | Stalactites hang from the sealing? of a limestone cave.|sup The density of quartz is 2.65 g/cm3.| | I was investigating the outcrop with my group.| Sodium sulfate forms a chalky, incoherent precipitate. amorphous?

v

| The density of gold is greater then? the density of silver.| Pyrite has a symmetrical crystal structure, it is cubic.| | Skarn mineral zonation? is apparent in the sample.

https://www.gimp.org/


ContentErrors in content are spelled out. Severe infractions may count for multiple errors.

Errors / Mistakes / Faults Examples with margin Fault Counter & Codes

Unclear / erroneous statements

False / nonsense

|unclear, units? Mohs hardness of the mineral in question is 16.5.

||Nonsense Glaciation cause severe metamorphism of the region


TABLES, FIGURES & EQUATIONS SUMMARY

Tables Each table must be sufficiently complete that it could stand on its own, separate from text.

Only HORIZONTAL lines are allowed in tables. Do NOT use any VERTICAL lines.

DO consecutively number and caption tables and refer to them accordingly within your text. Captionsgo ABOVE the table.DO provide a short description of your table within the caption.DO place your tables appropriately, closest to their mention in the text.DO make sure tables are legible and reproduce well. Print can be smaller than text, with an 8pt sizeminimum.DO appropriately label columns. Do NOT forget units for numeric values.

AVOID splitting tables across pages.

Figures Each figure must be sufficiently complete that it could stand on its own, separate from text.

DO number and caption figures consecutively and refer to them accordingly within your text. Captionsgo BELOW the figure.DO provide a short description of your figure within the caption.DO place your figures appropriately, closest to their mention in the text.DO use appropriate citations for figures that are NOT your own. If you use a figure that has beenmodified by you, the phrase “modified after....” is most appropriate. Photos should show the name ofthe photographer.DO make sure figures are legible and reproduce well. Print can be smaller than text, with an 8pt sizeminimum. Use a minimum resolution of 300dpi. This is a common publication standard.

AVOID cluttering of figures with too much detail. Simplify if necessary.AVOID moire patterns in photos, a nuisance in copied or scanned pictures. Most scanners come with amoire pattern removal tool.

GRAPHSUnderstand graphs: Bar graphs and/or line graphs are used when plotting nominal vs. ratio orinterval data. Scatter plot graphs are used when plotting numeric vs. numeric data.DO make sure that the graph axis are appropriately labeled and scaled. Axis should have titles as well asscalar units.DO use electronic means to generated graphs. Hand drawn graphs are no longer acceptable.

Equations &Computations

G Equations should contain explanation of symbols used.G A reader should be able to follow where your values or numbers come from. Indicate

accordingly.G WRITE DOWN UNITS!!!!G Show equations used before indicating any computation

Acceptable Example:

where m is mass of the object in kg as determined with a triple beam balanceand a is the gravitational acceleration. F indicates force expressed in kgm/s2

or N (Newtons).Unacceptable example: The answer is 0.33. This is obtained by multiplying gravity by 0.034.


PreambleCreating and Manipulating Graphics for Reports

GRAPHICS EDITOR SOFTWARE: You will need a graphics editor and learn how to use it. Windows comes with its defaultWindows Paint editor. It is found in the Windows Accessories Folder. For a more advanced option with many more professionalfeatures you may try GIMP: https://www.gimp.org/ This is a FREE, open source image editor working across all computingplatforms (Windows, Apple, Linux, etc.). The software comes with ample documentation and examples on how to manipulate anypicture or graphic.

SCREEN CAPTURE SOFTWARE: A screen capture or snipping software is advantageous in order to only grab the part of agraphic from the screen that is important or necessary. Windows 10 comes with a default snipping tools, such as “Snip & Sketch”

found in its own folder or “Snipping Tool” found in the Windows Accessaries Folder. Note: When snapping a picture, make sure it is large enough on the screen to capture enough pixels to haveadequate resolution for the final product.

ExampleOverview of graphic manipulation for XRF data processed through the S1PXRF software:

1. Obtain the complete dataand label the energy peaks.

Notice: The labels are toosmall for report presentationand much information isredundant. Therefore yourgraphic needs to bemanipulated.

2. Open your graphic in agraphics editor, such asWindows Paint as in thisexample:

https://www.gimp.org/


3. Use the Crop Function to eliminate any superfluous part in thegraphic by first selecting the area to be maintained (1) and thenclicking the crop symbol (2).

4. Add any relevant information, that was cut during cropping suchas voltages for the obtained spectra by using the Text Function (3).Make sure that the font is large enough to be crisp on your finalgraphic.

5. Replace any inadequatelabeling (too small, tooconfusing) by either

(a) erasing the original labelthrough the Erase Function(4) and then adding newlabels through the TextFunction (5) [shown on the left for Fe and Sr]

or (b) by saving / exporting the original XRF graph without theenergy peak labels, cropping it and then adding the labels later usingthe Text Function in the graphics editor (5).

6. Once completed, save your graphic as a .bmp or .tiff file. Theseare considered “loss-less” graphic formats. Try to avoid .jpg,because the compression algorithms will lose a little resolution

every time you edit and re-save a jpg file. Your final product should be of a good enough resolution (min.300dpi) to look crisp when printed.

Example of a finished graphic.

Note: The x-axis labels should have been edited as well toshow at least a 10pt font size when printed.

Comparison: 12pt 10pt 8pt 6pt


MINERAL ID LAB: DRY XRF & XRD ANALYSISXRF ANALYSIS


POPULATE AND COMPLETE THE FOLLOWING:

Description of Method (5 sentences or less):

Instruction:Using our Brucker Handheld XRF, run the sample analysis according to instruction. No special sample preparation is necessary.Make sure you test a FRESH sample surface only, especially in major element mode.

CAUTION: X-rays. Follow safety instructions! Note: Collected data and S1PXRF software will be emailed to you!

1 - Run a trace element scan: 40keV - No filters. Collect /record data.

2 - Run a major element scan: 15keV - No filters. Collect /record data.

3 - Open you pdz data files in S1PXRF. Manipulate the graph until an applicable overview of the sample analysis is portrayed.Label identified major peaks with the appropriate corresponding chemical element. You may have to manipulate

4 - Identify chemical elements as those unequivocally present and those occurring as trace amounts!

Check if CLIENT SAMPLE GYes GNo


[Insert Low Energy XRF Spectra - 15.00kV. Erase this text when inserting!] Elements present:

Probable Element Traces:

Comments:

[Insert High Energy XRF Spectra - 40.00kV. Erase this text when inserting!] Elements present:

Probable Element Traces:

Comments:

Note: Under “Comments” you may allude to restrictions of analysis, e.g. sample depth, etc, especially whenno spectra from a fresh surface can be obtained. This is most critical for Low Energy spectra! Clientslooking for elusive precious metals or similar should be reassured that the element(s) may be present butnot detected because of penetration depth and/or small analytical area of the whole sample.


MINERAL ID LAB: DRY XRF & XRD ANALYSISXRD SAMPLE PREP & RUN


POPULATE AND COMPLETE THE FOLLOWING:

Description of Method (5 sentences or less):

Instruction:Prepare a finely powdered sample according to the Lab Manual and mount in sample holder as instructed!

CAUTION: X-rays. Follow safety instructions! Note: Bring USB drive for data download. OurXRD unit uses an older computer with NO internet connection.

1 - Mount sample holder with sample in the XRD tray.

2 - Run XRD pattern scan. .

3 - Collect data, usually as a tab delimited ASCII file (.txt), as well as the XRD pattern graphic (bmp).

4 - Import the .txt file into Excel by opening the .txt file in a text editor (MS Notepad) and remove ALLheader down to the column data. Rename and save as a new .txt file.

5 - Now open this NEW .txt in Excel. You should get three columns A, B, C populated with numbers.Usually C is not needed and can be erased. Column “A” shows the 2theta angles and column “B” the X-ray intensities. Further processing of the file explained in the next segment. Check if CLIENT SAMPLE GYes GNo


MINERAL ID LAB: DRY XRF & XRD ANALYSISXRD DATA INTERPRETATION & REPORTING


XRD Data Plot and Analysis:

6 - Highlight Columns A and B and plot as XY (Scatter)Graph with A on the x-axis and B on the y-axis.

You will notice that the graph has very high countsaround 10E 2Theta interfering with the interpretation ofactual peaks and that the x-axis has a big empty spotbefore the 10E mark as shown in this example.

7 - Fix the graph by manipulating the x and y axis:7a - Set x axis starting value to 10; Label x axis7b - Set y axis maximum value a little bit over highestpeak, e.g.1200 and set lowest value to 0; Label y axis

8 - Remove chart title, since it is not needed. Save yourgraph in a graphics file format for later use.

9 - IMPORTANT: When you present your results usingthis graph with 2Theta angles plotted on the x-axis it isimperative that you MUST show the data for the X-Ray tube used, e.g. Type of tube and Ká and Kâwavelengths. There are multiple x-ray tubes in use and each tube will have peak patterns at differentlocations for the same mineral.

10 (optional) - In order to avoid the problem presentedunder #9 and for easy comparison with available mineralX-ray data patterns, it is advantageous to convert your x-axis data from 2Theta angles to d-spacings using Braggsequation. Manipulate your graph accordingly. However,by doing so, x-axis peaks will show in reverse order. Tofix this, adjust the x-axis format by checking the “plot inreverse order” box.

Hint: Braggs Equation processing in Excel when using a Cu X-ray tube. Place the following equation in Field C2, then

copy to all other fields in column C to end of data: =(1*1.5406)/(2*SIN(RADIANS(A2/2)))


XRD Data Plot and Analysis cont’d:

11 - GENERAL GRAPH INTERPRETATIONS: 11a - If your graph has NO peaks than you have an amorphous material with NO crystal structure, suchas glass, amber or opal.11b. - If you just have a few peaks with very high intensity counts you will probably have just a singlepure mineral (as in the example given above under #6 through #9).11c. - Smear slides (double sticky tape with mineral powder sprinkles for reconnaissance assessmentsor small sample quantities) will usually yield lower intensities from the get go, which may be harder tointerpret..11d. - If you get a good peak very early, around "2Theta" 10E to 13E, then you will most likely have a claymineral.11e. - If you have many peaks with lower intensity counts you will probably have a mixture of mineralscalled multiple phases. In this case you will need to separate the phases to positively identify an unknownmineral.

12 - SEPARATING PHASES: 12a - There is some software that will try to identify and separate multiple XRD phases automaticallyand can even provide estimated percentage concentrations for each phase. Most of these are comercialand rather expensive. One FREE software is called Xpowder and can be found at http://www.xpowder.com/. The use is limited to 300 days for free. Be aware that the learning curve forsome of these software solutions can be steep. 12b - You can separate phases manually using suspected mineral XRD data overlays. To do this go to theextensive and free RRUFF.org database at http://rruff.info/index.htm. Search for the suspected mineral and download its XRD data either as a graphic (2Theta vs Intensity Plot) and/or as RAW or ASCII files.The later you must process using the procedures explained under #6 through #9 above. IMPORTANT: The X-axis of both graphs, the unknown and the suspected known minerals MUSTmatch exactly in size / scale for this procedure to work. Therefore, create a graph or stretch or shrinkthe downloaded graphic to match the X-axis of your sample plot. Then see if you get an exact peakmatch. If you do, label these peaks with the identified mineral name and process remaining peaks forunknown mineral identification.

13 - Complete the analysis by picking the three highest peaks, setting the highest one to 100% and listtheir exact corresponding d-spacing as discussed during lecture and described in the manual. Those withindicated multiple phases will have to go through a process of peak elimination to do single phase(mineral) identification. Use the webmineral XRD site http://www.webmineral.com/help/XRayDiffraction.shtml and enter yourdata as discussed and shown in the manual.

http://www.xpowder.com/

http://rruff.info/index.htm

http://www.webmineral.com/help/XRayDiffraction.shtml


Note: Remove ALL text in square brackets [ ]!

XRD Analysis:

[(Paste your MEASURED XRD pattern graphic here)] [Label peaks especially for multiple phases]

X-ray Pattern

Major Peaks and d-spacing: [Sorted according to your measurement] 2 è

d D

I/I1 100

[leave the wavelength and Rad data presented here unless different x-ray tube is used] ë 1.5405 Rad: CuKá1

XRD pattern interpretation / comments:


CITATIONS: if applicable! ALL citations should be processed through the ZOTERO citationdatabase software, freely available at https://www.zotero.org/

As minimum citation, any software used and the RRUFF data base should be referenced!

Citations should follow the USGS citation standard!

GENERAL NOTES:• If you are using the CLIENT SAMPLE, then everything in the green framed fields needs to be transferred to your final

client report as indicated in the report outline and template.• Pay particular attention to the grading and comments / feedback associated with the green framed fields. Your grade

on the final report depends in part on you incorporating these corrections.

https://www.zotero.org/

MINERAL ID LAB: DRY XRF & XRD ANALYSIS

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